1 /* 2 * psb GEM interface 3 * 4 * Copyright (c) 2011, Intel Corporation. 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms and conditions of the GNU General Public License, 8 * version 2, as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 13 * more details. 14 * 15 * You should have received a copy of the GNU General Public License along with 16 * this program; if not, write to the Free Software Foundation, Inc., 17 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Authors: Alan Cox 20 * 21 * TODO: 22 * - we need to work out if the MMU is relevant (eg for 23 * accelerated operations on a GEM object) 24 */ 25 26 #include <drm/drmP.h> 27 #include <drm/drm.h> 28 #include <drm/gma_drm.h> 29 #include <drm/drm_vma_manager.h> 30 #include "psb_drv.h" 31 32 void psb_gem_free_object(struct drm_gem_object *obj) 33 { 34 struct gtt_range *gtt = container_of(obj, struct gtt_range, gem); 35 36 /* Remove the list map if one is present */ 37 drm_gem_free_mmap_offset(obj); 38 drm_gem_object_release(obj); 39 40 /* This must occur last as it frees up the memory of the GEM object */ 41 psb_gtt_free_range(obj->dev, gtt); 42 } 43 44 int psb_gem_get_aperture(struct drm_device *dev, void *data, 45 struct drm_file *file) 46 { 47 return -EINVAL; 48 } 49 50 /** 51 * psb_gem_dumb_map_gtt - buffer mapping for dumb interface 52 * @file: our drm client file 53 * @dev: drm device 54 * @handle: GEM handle to the object (from dumb_create) 55 * 56 * Do the necessary setup to allow the mapping of the frame buffer 57 * into user memory. We don't have to do much here at the moment. 58 */ 59 int psb_gem_dumb_map_gtt(struct drm_file *file, struct drm_device *dev, 60 uint32_t handle, uint64_t *offset) 61 { 62 int ret = 0; 63 struct drm_gem_object *obj; 64 65 mutex_lock(&dev->struct_mutex); 66 67 /* GEM does all our handle to object mapping */ 68 obj = drm_gem_object_lookup(dev, file, handle); 69 if (obj == NULL) { 70 ret = -ENOENT; 71 goto unlock; 72 } 73 /* What validation is needed here ? */ 74 75 /* Make it mmapable */ 76 ret = drm_gem_create_mmap_offset(obj); 77 if (ret) 78 goto out; 79 *offset = drm_vma_node_offset_addr(&obj->vma_node); 80 out: 81 drm_gem_object_unreference(obj); 82 unlock: 83 mutex_unlock(&dev->struct_mutex); 84 return ret; 85 } 86 87 /** 88 * psb_gem_create - create a mappable object 89 * @file: the DRM file of the client 90 * @dev: our device 91 * @size: the size requested 92 * @handlep: returned handle (opaque number) 93 * 94 * Create a GEM object, fill in the boilerplate and attach a handle to 95 * it so that userspace can speak about it. This does the core work 96 * for the various methods that do/will create GEM objects for things 97 */ 98 int psb_gem_create(struct drm_file *file, struct drm_device *dev, u64 size, 99 u32 *handlep, int stolen, u32 align) 100 { 101 struct gtt_range *r; 102 int ret; 103 u32 handle; 104 105 size = roundup(size, PAGE_SIZE); 106 107 /* Allocate our object - for now a direct gtt range which is not 108 stolen memory backed */ 109 r = psb_gtt_alloc_range(dev, size, "gem", 0, PAGE_SIZE); 110 if (r == NULL) { 111 dev_err(dev->dev, "no memory for %lld byte GEM object\n", size); 112 return -ENOSPC; 113 } 114 /* Initialize the extra goodies GEM needs to do all the hard work */ 115 if (drm_gem_object_init(dev, &r->gem, size) != 0) { 116 psb_gtt_free_range(dev, r); 117 /* GEM doesn't give an error code so use -ENOMEM */ 118 dev_err(dev->dev, "GEM init failed for %lld\n", size); 119 return -ENOMEM; 120 } 121 /* Limit the object to 32bit mappings */ 122 mapping_set_gfp_mask(r->gem.filp->f_mapping, GFP_KERNEL | __GFP_DMA32); 123 /* Give the object a handle so we can carry it more easily */ 124 ret = drm_gem_handle_create(file, &r->gem, &handle); 125 if (ret) { 126 dev_err(dev->dev, "GEM handle failed for %p, %lld\n", 127 &r->gem, size); 128 drm_gem_object_release(&r->gem); 129 psb_gtt_free_range(dev, r); 130 return ret; 131 } 132 /* We have the initial and handle reference but need only one now */ 133 drm_gem_object_unreference(&r->gem); 134 *handlep = handle; 135 return 0; 136 } 137 138 /** 139 * psb_gem_dumb_create - create a dumb buffer 140 * @drm_file: our client file 141 * @dev: our device 142 * @args: the requested arguments copied from userspace 143 * 144 * Allocate a buffer suitable for use for a frame buffer of the 145 * form described by user space. Give userspace a handle by which 146 * to reference it. 147 */ 148 int psb_gem_dumb_create(struct drm_file *file, struct drm_device *dev, 149 struct drm_mode_create_dumb *args) 150 { 151 args->pitch = ALIGN(args->width * ((args->bpp + 7) / 8), 64); 152 args->size = args->pitch * args->height; 153 return psb_gem_create(file, dev, args->size, &args->handle, 0, 154 PAGE_SIZE); 155 } 156 157 /** 158 * psb_gem_fault - pagefault handler for GEM objects 159 * @vma: the VMA of the GEM object 160 * @vmf: fault detail 161 * 162 * Invoked when a fault occurs on an mmap of a GEM managed area. GEM 163 * does most of the work for us including the actual map/unmap calls 164 * but we need to do the actual page work. 165 * 166 * This code eventually needs to handle faulting objects in and out 167 * of the GTT and repacking it when we run out of space. We can put 168 * that off for now and for our simple uses 169 * 170 * The VMA was set up by GEM. In doing so it also ensured that the 171 * vma->vm_private_data points to the GEM object that is backing this 172 * mapping. 173 */ 174 int psb_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 175 { 176 struct drm_gem_object *obj; 177 struct gtt_range *r; 178 int ret; 179 unsigned long pfn; 180 pgoff_t page_offset; 181 struct drm_device *dev; 182 struct drm_psb_private *dev_priv; 183 184 obj = vma->vm_private_data; /* GEM object */ 185 dev = obj->dev; 186 dev_priv = dev->dev_private; 187 188 r = container_of(obj, struct gtt_range, gem); /* Get the gtt range */ 189 190 /* Make sure we don't parallel update on a fault, nor move or remove 191 something from beneath our feet */ 192 mutex_lock(&dev->struct_mutex); 193 194 /* For now the mmap pins the object and it stays pinned. As things 195 stand that will do us no harm */ 196 if (r->mmapping == 0) { 197 ret = psb_gtt_pin(r); 198 if (ret < 0) { 199 dev_err(dev->dev, "gma500: pin failed: %d\n", ret); 200 goto fail; 201 } 202 r->mmapping = 1; 203 } 204 205 /* Page relative to the VMA start - we must calculate this ourselves 206 because vmf->pgoff is the fake GEM offset */ 207 page_offset = ((unsigned long) vmf->virtual_address - vma->vm_start) 208 >> PAGE_SHIFT; 209 210 /* CPU view of the page, don't go via the GART for CPU writes */ 211 if (r->stolen) 212 pfn = (dev_priv->stolen_base + r->offset) >> PAGE_SHIFT; 213 else 214 pfn = page_to_pfn(r->pages[page_offset]); 215 ret = vm_insert_pfn(vma, (unsigned long)vmf->virtual_address, pfn); 216 217 fail: 218 mutex_unlock(&dev->struct_mutex); 219 switch (ret) { 220 case 0: 221 case -ERESTARTSYS: 222 case -EINTR: 223 return VM_FAULT_NOPAGE; 224 case -ENOMEM: 225 return VM_FAULT_OOM; 226 default: 227 return VM_FAULT_SIGBUS; 228 } 229 } 230